<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>双飞翼</title>
	<style>
	.main-wrapper {
		float: left;
		width: 100%;
	}
	.main {
		height: 300px;
		margin-left: 210px;
		margin-right: 190px;
		background-color: red;
	}
	.sub {
		float: left;
		width: 200px;
		height: 300px;
		margin-left: -100%;
		background-color: blue;
	}
	.extra {
		float: left;
		width: 180px;
		height: 300px;
		margin-left: -180px;
		background-color: pink;
	}
	</style>
</head>
<body>
	<div class="main-wrapper">
		<div class="main"></div>
	</div>
	<div class="sub"></div>
	<div class="extra"></div>

</body>
</html>
